Radiant gas burner



Dec. 19, 1961 o. HEIMERL RADIANT GAS BURNER Filed Sept. 18, 1956 FIG. 2

FIG.

FIG. 4

I r ll ATTORNEYS 3,013,602 Patented Dec. 19, 1961 tire 4 3,013,602RADEANT GAS BURNER (Etta Heimerl, Kola Kath, Germany, assignor toAmerican Infra Red Radiant (30., inc, Houston, Tex., a corporation atDelaware Fiied Sept. 18, 1956, Ser. No. 610,467 4 Claims. (Cl. 158-414)The present invention relates to gas heating appliances.

In gas heating appliances of the type to which the present inventionrelates, provision is made for a radiation burner or radiator having aplate-like gas permeable closure. This closure is rendered incandescentby the combustion of gas on its surface. The resultant heat, transmittedprimarily by radiation, may be used for heating, cooking or for medicaland therapeutic purposes. The gas-air mixture is supplied to the burnerchamber, formed by the radiator housing and the burner closure plate, bya mixer pipe, which has its outer end disposed outwardly of the housingand which outer end is provided with an injector through which thepassing gas draws in the requisite air to provide the gas-air mixture.

It was formerly believed that in order to achieve thorough mixture ofthe gas with the air, a maximum length of common flow path of the gasand the air, between the point of combination thereof in the injectorand the point of emergence thereof into the chamber, was required. Themixer pipe in gas mixers of the prior art extends substantially over theentire length of the burner chamber and does not open into the burnerchamber until its innermost end, just ahead of the end wall of theburner chamber transverse to the mixer pipe. At the point of emergence,the major portion of the gas-air mixture is deflected by 180 degrees sothat at this point a considerable static pressure and an undesirablestagnation of the mixture results. The pressure distribution in theburner chamber becomes non-uniform, with resulting non-uniformity of theflow of gas undergoing combustion per unit area. Since, in various partsof the burner chamber, a substantially lower pressure of gas-air mixtureis established than elsewhere in the burner chamber, this mixture willflow through the burner closure plate at those points, where the latterwill therefore be heated to a lower temperature than the rest of theradiation surface.

In view of the foregoing, it-is an object of the present invention toobviate the foregoing disadvantages of the prior art.

Pursuant to the foregoing object, it is another object of the inventionto provide a mixer pipe which has, over most of the extent thereof whichis disposed in the burner chamber, means for providing outlets for thegas-air mixture within the burner chamber.

The above and other objects, features and advantages of the presentinvention will be more fully understood from the following descriptionconsidered in connection with the accompanying illustrative drawings.

In the drawings which illustrate the best modes presently contemplatedof carrying out the invention:

FIG. 1 is a top plan view of a burner pursuant to the present invention,parts being omitted for purposes of illustration;

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on the line 33 of FIG. 1;

FIG. 4 is a view similar to FIG. 3 and illustrates a modification; and

FIG. 5 is a view similar to FIG. 2, but with parts omitted andillustrates another modification.

The present invention is based upon the realization or discovery thatthe achievement of a thorough mixture of common flow path for both thegas and the air, but rather primarily a deflection with some degree ofvortex forma-.

tion. Since, in accordance with the present aspect of the invention, themixture of gas and air enters the burner chamber of the gas heatingappliance over much of the total length of the mixer pipe, or even overall of it, a very uniform pressure disposition is established in thechamber, resulting in a uniform temperature distribution over the entiresurface of the burner closure plate. Through avoidance of deflection ofthe emerging mixture by degrees, no static pressure is generated at thepoint of emergence of the mixture pipe, and the flow resistance of theburner is substantially diminished. This is of great importance withrespect to the low pressure of gas used in such heating appliances, asit augments the gas capacity and hence the heating power of theappliance.

Referring now to FIGS. 1, 2 and 3 of the drawings in detail, there isillustrated a gas heating appliance 20 pursuant to the presentinvention. The appliance 20 is provided with a burner closure wall 22which is composed of four gas permeable plates 24, of which only oneplate is illustrated herein. The burner elements or members 24 arepreferably of the type illustrated and described in the copendingapplication of Gunther Schwank, Serial Number 214,468, filed March 8,1951, and assigned to the assignee hereof, now Patent No. 2,775,294,granted December 25, 1956. The burner elements 24 sit loosely in a frame26. The frame extends completely about the burner wall 22, beingprovided with an inturned flange 28 which overlies the front surfaces ofthe burner elernents 24 and which is provided with an inner surface 30which provides a lateral bearing surface for the various burnerelements. The frame i also provided with integral cross pieces orpartitions 32 and 34 respectively, so as to define with the outerperiphery of the frame the separate box like compartments 36, each ofwhich accommodates one burner element 24.

Provision is made for a housing 38 which is of generally dished ortub-like conformation. The housing 38 is provided with a lateral flangeor rim 40 on which there is engaged a complementary flange or rim 42provided on the frame 26, said rims being secured together in anysuitable manner, for example by screws (not illustrated). The housing 38is also provided with a column or post 44 which extends from the floor46 thereof. It will be noted from FIGS. 1 and 2 that each burner element24 is supported between the frame 26 and the upper surface or face 48 ofthe flange 40. In this connection, it will be apparent that each burnerelement is disposed on said face 48 along two of the marginal edgesthereof and it will be noted that the four adjacent inside corners 50 ofthe burner elements 24 are supported by the post 44.

The mixer or pipe 52 for the combustion mixture, as here shown,comprises a substantially semi-circularly curved sheet of metal 54 andthe confronting floor 46 of the burner housing 38. The pipe has a gap orslot 56 which opens into the burner chamber 58 and is also provided withan opening 60 for the column 44. Should it be necessary to reduce theresistance to the flow in the mixing tube 52 which is offered by thepost 44, the post may either be streamlined or it may consist of arelatively narrow part which extends through the mixer pipe 52 and asupporting plate may be provided on the top thereof. The mixer pipe issupported at one end thereof by a projection or boss 62 which is castinto one end wall of the burner housing, and at the other end thereof bya boss or projection 64 which is cast into the other end wall of theburner housing, the sheet metal part 54 being secured to the boss 64 asby the bolt 66. Pipe 52 extends longitudinally of housing 38 forsubstantially the full length thereof and increases progressively incross sectional area longitudinally thereof in a direction extendingfrom its inlet at boss 62, as best seen in FIG. 1. The gas-air mixernozzle is indicated by the reference numeral 68 and the gas supply lineis indicated at 70.

In the embodiment illustrated in FIG. 4, the mixer tube comprises also asubstantially semi'circularly curved sheet of metal 54' and a portion 74of the floor 46' of the burner housing 38'. It will be noted that theportion 74 is shaped so as to conform to the semi-circular shape of thepart 54 so as to provide a mixer tube 52 which is almost circular incross section.

In the embodiments illustrated in FIGS. 3 and 4, the outlet port oropening in the mixer tube, which communicates with the burner chamber,comprises the gap or slot 56 which is defined on each side of the mixerpipe, longitudinally thereof, just above the floor of the housing.However, it is within the scope of the present in vention, to provideseparate holes or apertures 56 (FIG. 5), in lieu of the continuous slotor gap 56, some of which apertures may, if desired, he provided at thetop of the semi-circular part 54. In addition, it is within the scope ofthe present invention to use structural parts other than curved sheetmetal for the parts 54 and 54'. For example, and not by way oflimitation, castings may be used in lieu of said metallic parts.

It will be apparent that all of the burner elements 24, whichcollectively define the cover plate 22, may be removed from the frame 26and said elements may be replaced when the frame is removed from theburner housing 38. Once the frame has been removed, the interior of theburner chamber 58 is readily accessible and it will be apparent thatafter the bolt 66 is loosened or removed, the interior or inner surfacesof the mixing tube 52 are also readily accessible.

The frame 26 may be formed in any suitable manner. For example, it maybe made of cast iron, it may be injection die cast, or it may consist ofbars which are welded together, or the frame may be stamped out of sheetmetal.

While I have shown and described the preferred embodiments of myinvention, it will be understood that various changes may be made in thepresent invention without departing from the underlying idea orprinciples of the invention within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. In a radiant heater, comprising a casing having an inlet for acombustible gaseous mixture and an outlet opening for said combustiblemixture, and gas-permeable closure and burner means mounted on saidcasing over said opening and providing a radiant burner surfaceexternally thereof,'said casing having an internal wall spaced from andin confronting relation to said closure and burner means; tubular meansdisposed in said casing in the space between said burner means and saidinternal wall and connected to said inlet for distributing the gaseousmixture to said burner means for passage therethrough, said tubularmeans extending longitudinally of said casing for substantially the fulllength thereof and increasing progressively in cross sectional arealongitudinally thereof in a direction extending from said inlet, saidtubular means having an external wall surface in spaced confrontingrelation with the inner surface of said burner means and having outletmeans along substantially the full length of said tubular means, saidexternal wall surface being laterally curved and extending from saidoutlet means in a direction toward said inner surface of said burnermeans, so that said gaseous mixture is discharged from said outlet meansin streamline fashion along substantially the full length of saidtubular means for distributing said gaseous mixture at substantiallyuniform pressure over the area of the inner surface of said burnermeans, said outlet means being substantially closer to said internalwall of said casing than to the inner surface of said burner means.

2. A radiant heater according to claim 1, further characterized in thatsaid tubular means has a laterally curved internal wall surface, saidinternal wall of said casing having a laterally curved portion inconfronting and spaced relation with said internal wall surface of saidtubular means, said space between said laterally curved portion of saidcasing and said internal wall surface of said tubular means providingsaid outlet means of said tubular means.

3. A radiant heater according to claim 1, further characterized in thatsaid outlet means comprises laterally spaced openings extending alongsubstantially the full length of said tubular means.

4. A radiant heater according to claim 1, further characterized in thatsaid casing has opposite side walls spaced laterally of said tubularmeans and supports said burner means in position in spaced relation tosaid tubular means adjacent the latter, and in the provision of aremovable frame for removably securing said burner means to said casingin said position.

References Cited in the file of this patent UNITED STATES PATENTS595,988 Brock Dec. 21, 1897 740,150 Lawler Sept. 29, 1903 1,507,791Packer Sept. 9, 1924 1,630,878 Wilson May 31, 1927 1,682,148 RisingerAug. 28, 1928 1,812,315 Baumgartner June 30, 1931 2,037,496 Bryant Apr.14, 1936 2,242,742 Bobo May 20, 1941 2,395,868 Hahn Mar. 5, 19462,543,688 Coriolis et al. Feb. 27, 1951 2,572,273 Miller Oct. 23, 19512,755,851 Dow et al. July 24, 1956 2,775,294 Schwank Dec. 25, 19562,832,331 Schwank Apr. 29, 1958 FOREIGN PATENTS 494,087 Great BritainOct. 17, 1938 741,660 Great Britain Dec. 7, 1955

